(1) Field of the Invention
The present invention relates to a liquid crystal panel, a plasma display panel, and a wide-screen liquid crystal television.
(2) Description of the Related Art
In recent years, panel-type televisions such as liquid crystal televisions and plasma televisions have become remarkably widespread. While such a liquid crystal television and a plasma television have common functions in a video signal processing function, an audio signal processing function, a power supply circuit, and an input and output circuit, both types of televisions are manufactured based on their specific designs. This is because both types of televisions adopt their respective optimum circuit components and layouts thereof However, this design method increases design man-hours, and therefore prevents an improvement in design efficiency. As a matter of course, in each panel-type television, products of similar sizes such as 26 inches and 27 inches have commonality of boards and components.
The following are known techniques for providing commonality of boards and components. Japanese Unexamined Patent Application Publication No. 2006-129167 describes a technique of using an AV circuit board in common between a digital circuit board capable of receiving a charging broadcast and a digital circuit board incapable of receiving a charging broadcast. Japanese Unexamined Patent Application Publication No. 2003-110965 describes a technique of providing commonality of boards by forming mounting holes respectively for tuners of different terminal arrangements and connecting the corresponding mounting holes. Japanese Unexamined Patent Application Publication No. 2003-61009 describes a technique in which circuit components in common between a digital television and a digital television set-top box are formed on a first board, circuit components specific to each device are formed on a second board, and connections are made by wiring.
Conventionally, each panel-type television has commonality of boards and components; however, there is no commonality of board structures between the liquid crystal television and the plasma television. This is due to the following reasons.
First, there exist circuits that are necessary to either one of the liquid crystal television and the plasma television but unnecessary to the other one, which makes the design commonality difficult. For example, the liquid crystal television requires an inverter circuit and its dedicated power supply, whereas the plasma television does not require an inverter circuit.
Further, for commonality of board structures, problems with destinations and noise also exist. Nowadays, televisions are shipped to multiple countries (e.g., Japan, Europe, and US), requiring major design changes to conform to the broadcast systems of these countries. While a digital processing circuit is resistant to noise, a circuit for transmitting an analog input and output signal and the like is susceptible to noise and needs to be laid out apart from an inverter circuit and a power supply circuit which are likely to be noise sources.